The dimethylsulfoxonium methylide as unique reagent for the simultaneous deprotection of amino and carboxyl function of N-Fmoc-α-amino acid and N-Fmoc-peptide esters

The dimethylsulfoxonium methylide is described as a unique and useful reagent for the simultaneous deprotection of amino and carboxyl function of N-Fmoc-α-amino acid and N-Fmoc-peptide esters. The new methodology was applied successfully both to solution- and solid-phase peptide synthesis. The adopted methodology was extended successfully also to peptides containing amino acids bearing acid-sensitive protecting group in side chains. Furthermore no measurable epimerization was observed in the deprotection reaction of N-Fmoc-dipeptide methyl esters with dimethylsulfoxonium methylide.